Such a friction coefficient measurement apparatus as mentioned above is proposed by the applicant of the present application (see Patent Literature 1) and is a measurement apparatus which accurately measures a friction coefficient over a wide velocity range from a high velocity to a low velocity and which is easy to carry to a measurement site.
A strip to which road surface friction measuring rubber is attached (hereinafter, referred to as the road surface friction measuring rubber attached strip) of this friction coefficient measurement apparatus is a consumption article and it is requested to exchange the strip with new one every time in a case that the rubber has been worn down due to friction between the rubber and the road surface.
When exchanging the road surface friction measuring rubber attached strip with the new one, first, an attaching bolt which is disposed on one end of the road surface friction measuring rubber attached strip is detached (unscrewed) from a main body of the friction coefficient measurement apparatus. Then, the road surface friction measuring rubber attached strip that a rubber part has been worn down is exchanged with the new one (another road surface friction measuring rubber attached strip that the rubber part is not worn down) and the new one is attached to the main body of the friction coefficient measurement apparatus by screwing the attaching bolt into the friction coefficient measurement apparatus main body.
Here, since the attaching bolt is comparatively small, procedure of detaching the attaching bolt from the friction coefficient measurement apparatus main body and screwing the attaching bolt again into the apparatus main body are complicated. Then, it is necessary to store the attaching bolt which has been detached from measurement apparatus main body somewhere while exchanging the road surface frictional measuring rubber attached strip with the new one and labor taken for performing the work is increased by such the necessity.
Further, it sometimes occurs that the attaching bolt which has been detached from the measurement apparatus main body is fallen downwardly when exchanging the road surface frictional measuring rubber attached strip with the new one. There are many cases where measurement of the friction coefficient using the above-mentioned friction coefficient measurement apparatus is carried out at night, and then, it is difficult to find the attaching bolt in a case that the attaching bolt has been fallen downwardly at night.
Accordingly, although there is a request to reduce the operator taken for performing the procedures of exchanging the road surface friction measuring rubber attached strip with the new one, a technology which is able to apply to such a request has not been proposed yet.